U.S. patent application number 13/266543 was filed with the patent office on 2012-05-24 for cooking apparatus using microwaves.
Invention is credited to Heung Sik Choi, Jin Yul Hu, Wan Soo Kim, Hyun Wook Moon, Sung Hun Shim.
Application Number | 20120125921 13/266543 |
Document ID | / |
Family ID | 43356950 |
Filed Date | 2012-05-24 |
United States Patent
Application |
20120125921 |
Kind Code |
A1 |
Shim; Sung Hun ; et
al. |
May 24, 2012 |
COOKING APPARATUS USING MICROWAVES
Abstract
The present invention relates to a cooking apparatus using
microwaves. The cooking apparatus using microwaves according to an
embodiment of the present invention, comprises: a microwave
generator which generates a plurality of microwaves to heat an
object inside a cavity and then outputs the generated microwaves;
and a controller which calculates heating efficiency with respect
to each of the plurality of microwaves based on the microwaves
reflected from the inside of the cavity among the outputted
microwaves, and then sets heating time with respect to each
microwave during a heating period of time according to the
calculated heating efficiency.
Inventors: |
Shim; Sung Hun;
(Geumchun-ku, KR) ; Hu; Jin Yul; (Geumchun-ku,
KR) ; Moon; Hyun Wook; (Geumchun-ku, KR) ;
Choi; Heung Sik; (Geumchun-ku, KR) ; Kim; Wan
Soo; (Geumchun-ku, KR) |
Family ID: |
43356950 |
Appl. No.: |
13/266543 |
Filed: |
June 18, 2010 |
PCT Filed: |
June 18, 2010 |
PCT NO: |
PCT/KR2010/003982 |
371 Date: |
February 9, 2012 |
Current U.S.
Class: |
219/702 |
Current CPC
Class: |
Y02B 40/146 20130101;
Y02B 40/143 20130101; Y02B 40/00 20130101; H05B 6/705 20130101;
H05B 6/686 20130101 |
Class at
Publication: |
219/702 |
International
Class: |
H05B 6/68 20060101
H05B006/68 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 19, 2009 |
KR |
1020090055168 |
Jun 19, 2009 |
KR |
1020090055170 |
Sep 1, 2009 |
KR |
1020090082004 |
Claims
1. A cooking apparatus using microwaves, comprising: a microwave
generator which generates a plurality of microwaves to heat an
object inside a cavity and then outputs the generated microwaves;
and a controller which calculates heating efficiency with respect
to each of the plurality of microwaves based on the microwaves
reflected from the inside of the cavity among the outputted
microwaves, and then sets heating time with respect to each
microwave during a heating period of time according to the
calculated heating efficiency.
2. The cooking apparatus of claim 1, wherein the controller
controls such that when the heating efficiency of a first microwave
among the plurality of microwaves is higher than that of a second
microwave, the heating time of the first microwave is set to be
shorter than that of the second microwave.
3. The cooking apparatus of claim 1, wherein the microwave
generator outputs a constant power with respect to each of the
plurality of microwaves during the heating period of time.
4. The cooking apparatus of claim 1, wherein the controller
supplies the same power control signal with respect to the each
microwave to the microwave generator during the heating period of
time.
5. The cooking apparatus of claim 1, wherein the microwave
generator sequentially generates the plurality of microwaves for
heating the object inside the cavity and outputs the generated
microwaves.
6. The cooking apparatus of claim 1, wherein the controller
controls such that the heating time with respect to the each
microwave is set during the heating period of time by selecting
only microwaves that the calculated heating efficiency is equal to
or higher than a criterion efficiency.
7. The cooking apparatus of claim 1, wherein the controller
controls such that the heating efficiency is calculated in a scan
period of time among the cooking process using microwaves including
the scan period of time and the heating period of time.
8. A cooking apparatus using microwaves, comprising: a microwave
generator which generates microwaves to heat an object inside a
cavity and then outputs the generated microwaves; and a controller
which uses the microwaves when heating by selecting the microwaves
of frequencies corresponding to the heating efficiency down
adjusted by setting value from the maximum heating efficiency when
the microwaves of frequencies that a heating efficiency is equal to
or greater than a threshold value, based on the microwaves
reflected from the inside of the cavity among the outputted
microwaves, do not exist.
9. The cooking apparatus of claim 8, wherein the controller
controls such that in the scan period of time among the cooking
process using microwaves including the scan period of time and the
heating period of time, microwaves of frequencies to be used during
the heating period of time are selected.
10. The cooking apparatus of claim 8, wherein the microwave
generator sequentially generates the plurality of microwaves for
heating the object inside the cavity and outputs the generated
microwaves.
11. The cooking apparatus of claim 8, further comprising: a
microwave transmitter for transmitting the microwaves generated by
the microwave generator to the inside of the cavity.
12. The cooking apparatus of claim 8, wherein the controller
controls such that when the microwaves having frequencies that a
heating efficiency is equal to or greater than a threshold value,
based on the microwaves reflected from the inside of the cavity
among the outputted microwaves, do not exist, the threshold value
is down adjusted.
13. The cooking apparatus of claim 12, wherein the controller
controls such that during the scan process for selecting the
microwaves having frequencies to be used when heating, and the
presence of the microwaves having frequencies that the heating
efficiency is equal to or greater than the threshold value is
identified.
14. The cooking apparatus of claim 12, wherein the controller
controls such that when the threshold value is down adjusted, the
microwaves having frequencies to be used when heating according to
the down adjusted threshold value are selected by re-performing the
scan process.
15. A cooking apparatus using microwaves, comprising: a microwave
generator which generates a plurality of microwaves to heat an
object inside a cavity and then outputs the generated microwaves;
and a controller controls such that a heating mod is selected
according to a heating efficiency calculated on the basis of the
microwaves reflected from the inside of the cavity among the
outputted microwaves, and the same energy is supplied by the
selected heating mode.
16. The cooking apparatus of claim 15, wherein the controller
controls such that the heating mode is selected on the basis of a
peak value of the calculated heating efficiency.
17. The cooking apparatus of claim 15, wherein the controller
controls such that the heating mode is selected on the basis of a
predetermined threshold value for the calculated heating
efficiency.
18. The cooking apparatus of claim 15, wherein the controller
controls such that the same energy is supplied for each of
microwaves having frequencies corresponding to a peak value of the
calculated heating efficiency.
19. The cooking apparatus of claim 15, wherein the controller
controls such that the total energy is equally supplied by each of
the selected heating modes by supplying the heating energy to be
inversely proportional to the frequency range for each of the
selected heating modes.
20. The cooking apparatus of claim 15, wherein the microwave
generator outputs a constant power for each of the microwaves
corresponding to the selected modes during the heating period of
time.
Description
TECHNICAL FIELD
[0001] The present invention relates to a cooking apparatus using
microwaves, and more particularly, to a cooking apparatus using
microwaves for selecting microwaves used when heating.
BACKGROUND ART
[0002] In general, in a cooking apparatus using microwaves, after
closing received foods, when pressing an operation button, a
voltage is applied to a high voltage generator. In this case, a
commercial voltage applied to the high voltage generator is boosted
and the power is applied to a magnetron to generate microwaves, and
the microwaves generated by the magnetron are transmitted to a
cavity through a waveguide.
[0003] At this point, the cooking apparatus using microwaves heats
food through frictional heat generated by vibrating the molecules
composed of the food by two billions and five million times per
second after irradiating the food with microwaves generated from
the magnetron.
[0004] The cooking apparatus using microwaves is widespread in a
home due to various advantages such as ease of the temperature
control, cooking time savings, ease of operation and the like.
DISCLOSURE
Technical Problem
[0005] An object of the present invention is to provide a cooking
apparatus using microwaves wherein an uniform power can be
transmitted to an object inside a cavity by decreasing a heating
time for microwaves having a high heating efficiency and increasing
the heating time for microwaves having a low heating
efficiency.
[0006] Meanwhile, another object of the present invention is to
provide a cooking apparatus using microwaves wherein even when the
microwaves of frequencies that a calculated heating efficiency
during an initial scan is equal to or greater than a threshold
value do not exist, the scan tine can be shortened by effectively
selecting the microwaves of frequencies using when heating.
[0007] In addition, yet another object of the present invention is
to provide a cooking apparatus using microwaves wherein the object
inside the cavity can be uniformly heated by controlling such that
the heating mode is selected according to the heating efficiency
and the same energy is supplied by the selected heating mode.
Technical Solution
[0008] In order to solve the aforementioned problem, there is
provided a cooking apparatus using microwaves according to an
embodiment of the present invention, including: a microwave
generator which generates a plurality of microwaves to heat an
object inside a cavity and then outputs the generated microwaves;
and a controller which calculates heating efficiency with respect
to each of the plurality of microwaves based on the microwaves
reflected from the inside of the cavity among the outputted
microwaves, and then sets heating time with respect to each
microwave during a heating period of time according to the
calculated heating efficiency.
[0009] In addition, there is provided a cooking apparatus using
microwaves according to an embodiment of the present invention,
including: a microwave generator which generates a plurality of
microwaves to heat an object inside a cavity and then outputs the
generated microwaves; and a controller which uses microwaves when
heating by selecting the microwaves of frequencies corresponding to
the heating efficiency down adjusted by setting value from the
maximum heating efficiency when the microwaves of frequencies that
a heating efficiency is equal to or greater than a threshold value,
based on the microwaves reflected from the inside of the cavity
among the outputted microwaves, do not exist.
[0010] In addition, there is provided a cooking apparatus using
microwaves according to an embodiment of the present invention,
including: a microwave generator which generates a plurality of
microwaves to heat an object inside a cavity and then outputs the
generated microwaves; and a controller controls such that a heating
mod is selected according to a heating efficiency calculated on the
basis of the microwaves reflected from the inside of the cavity
among the outputted microwaves, and the same energy is supplied by
the selected heating mode.
Advantageous Effects
[0011] According to the cooking apparatus using microwaves of the
present invention, the present invention has the following effects
one or more.
[0012] Firstly, an uniform power can be transmitted to an object
inside a cavity by decreasing a heating time for microwaves having
a high heating efficiency and increasing the heating time for
microwaves having a low heating efficiency. Further, the cost can
be reduced by maintaining a constant power during a heating period
of time using microwaves without including additional power control
devices.
[0013] Secondly, even when the microwaves of frequencies that a
calculated heating efficiency during an initial scan is equal to or
greater than a threshold value do not exist, the scan tine can be
shortened by effectively selecting the microwaves of frequencies
using when heating.
[0014] Thirdly, the object inside the cavity can be uniformly
heated by controlling such that the heating mode is selected
according to the heating efficiency and the same energy is supplied
by the selected heating mode.
[0015] The effects of the present invention are not limited to the
above-mentioned effects and further effects not described above
will be clearly understood by those skilled in the art.
DESCRIPTION OF DRAWINGS
[0016] FIG. 1 is a partial perspective view illustrating a cooking
apparatus using microwaves according to an embodiment of the
present invention.
[0017] FIG. 2 is a cross-sectional view illustrating the cooking
apparatus shown FIG. 1.
[0018] FIG. 3 is a block diagram illustrating the inside of the
cooking apparatus shown FIG. 1.
[0019] FIG. 4 is a view illustrating an example of changes in
frequencies during cooking including a scan period of time and a
heating period of time.
[0020] FIG. 5 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to an embodiment of
the present invention.
[0021] FIGS. 6 and 7 are views for referring to the description of
FIG. 5.
[0022] FIG. 8 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to another embodiment
of the present invention.
[0023] FIG. 9 is a view for referring to the description of FIG.
8.
[0024] FIG. 10 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to another embodiment
of the present invention.
[0025] FIG. 11 is a view for referring to the description of FIG.
10.
[0026] FIG. 12 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to another embodiment
of the present invention.
[0027] FIGS. 13 and 14 are views for referring to the description
of FIG. 12.
[0028] FIG. 15 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to another embodiment
of the present invention.
[0029] FIGS. 16 to 23 are views for referring to the description of
FIG. 15.
BEST MODE
[0030] Exemplary embodiments of the present invention will now be
described in detail with reference to the accompanying
drawings.
[0031] In the following description, usage of suffixes such as
`module`, `part` or `unit` used for referring to elements is given
merely to facilitate explanation of the present invention, without
having any significant meaning by itself. Thus, the `module` and
`part` may be mixedly used.
[0032] FIG. 1 is a partial perspective view illustrating a cooking
apparatus using microwaves according to an embodiment of the
present invention, and FIG. 2 is a cross-sectional view
illustrating the cooking apparatus shown FIG. 1.
[0033] Referring to FIGS. 1 and 2, in the cooking apparatus 100
using microwaves according to the embodiment of the present
invention, a door 106 on which a cooking window 104 is attached is
coupled to the front portion of the main body 102 to be closed or
opened and a operating panel 108 is coupled to one side portion of
the front of the main body 102.
[0034] The door 106 closes and opens a cavity 134. Although not
shown in drawings, the inside of the door 160 may be provided a
filter (not shown) for shielding of the microwaves.
[0035] The operating panel 180 includes an operating unit 107
operating operations of the cooking apparatus and a display unit
105 displaying the operations of the cooking apparatus.
[0036] The inside of the main body 102 is provided with the cavity
134 having a receiving space of a predetermined size to cook a
heating object 140, for example, foods by microwaves
[0037] In addition, the outside surface of the cavity 134 is
installed with a microwave generator 110 for generating microwaves
and an output side of the microwave generator 110 is disposed with
a microwave transmitter 112 for guiding microwaves generated from
the microwave generator 110 to the inside of the cavity 134.
[0038] The microwave generator 110 may include a magnetron, or a
solid state power amplifier (SSPA) using a semiconductor. The solid
state power amplifier (SSPA) has an advantage of occupying less
space than the magnetron.
[0039] Meanwhile, the solid state power amplifier (SSPA) can be
implemented with a hybrid microwave integrated circuits (HMIC)
including an additional passive elements (capacitors or inductors)
or active elements (transistors) for amplification, or a monolithic
microwave integrated circuits (MMIC) on which the passive elements
and the active elements are implemented as one substrate.
[0040] Meanwhile, according to the embodiment of the present
invention, the microwave generator 110 may generate and output a
plurality of microwaves. The range of frequency of the microwave
may be approximately 900 MHz to 2,500 Hz. In particular, the range
of frequency of the microwave may be in a predetermined range
around 915 MHz or around 2,450 MHz. The microwave generator 110 is
described in detail with reference to FIG. 3 below.
[0041] The microwave transmitter 112 transmits microwaves outputted
form the microwave generator 110 to the cavity 134. The microwave
transmitter 112 may include a waveguide or a coaxial line. In order
to transmit the generated microwaves to the microwave transmitter
112, a coupling unit 142 is connected as shown in the drawings.
[0042] Meanwhile, the microwave transmitter 112 may be implemented
in the opened form having an opening 145 inside the cavity 134 as
shown in the drawings, but it is not limited to thereof and an
antenna can be coupled to the end. The opening 145 may be formed in
various types such as a slot and the like. The microwaves are
discharged to cavity 134 through the opening 145 or the antenna.
Thus, the portion discharging the microwaves into the cavity 134 is
called as a feeder and may include the opening or the antenna.
[0043] Meanwhile, in the drawings, only the opening 145 disposed on
the upper side of cavity 134 is shown, but the opening 145 may be
disposed on the lower or the side portion of the cavity 134 and a
plurality of openings may be disposed. Further, it may be coupled
through the antenna instead of the opening 145.
[0044] The lower side of the microwave generator 110 is provided
with a power supply 114 which supplies power to the microwave
generator 110
[0045] The power supply 114 may include a high voltage transformer
which supplies a high voltage to the microwave generator 110 by
boosting power inputted to the cooking apparatus 100, or an
inverter which supplies approximately 3500V or more high output
voltage generated by performing switching operations of at least
one switching elements to the microwave generator 110.
[0046] Meanwhile, the vicinity of the microwave generator 110 may
be installed with a cooling fan (not shown) which cools the
microwave generator 110
[0047] Although not shown in the drawings, the inside of the cavity
134 is installed with a turntable (not shown) which rotates the
heating object 140, or the inside of the cavity 134 is provided
with a stirrer fan (not shown) which distributes the microwaves and
a cover (not shown) which prevents damage of the stirrer fan (not
shown). The stirrer fan (not shown) can mean a kind of antenna
described above.
[0048] The cooking apparatus 100 using the microwaves as described
above is operated when being pressed a cooking selection button
(not shown) and a start button (not shown) by operating an
operation panel 108, in particular, an operating unit 107 in a
state that the door 106 is closed, after the user opens the door
106 and inserts the heating object 104 in the cavity 134.
[0049] That is, the power supply 114 of the cooking apparatus 100
boosts the inputted AC power to high voltage DC power and supplies
the high voltage DC power to the microwave generator 110, the
microwave generator 110 generates and outputs the corresponding
microwaves, and the microwave transmitter 112 transmits and
discharges the generated microwaves to the cavity 134. Accordingly,
the heating object 140 for example, foods provided inside the
cavity 134 is heated. The overall operation of the cooking
apparatus 100 may be performed by a controller (not shown). The
controller (not shown) is described with reference to the drawings
below.
[0050] FIG. 3 is a block diagram briefly illustrating the inside of
the cooking apparatus shown FIG. 1. In addition, FIG. 4 is a view
illustrating an example of changes in frequencies during cooking
including a scan period of time and a heating period of time.
[0051] Referring to the drawings, the cooking apparatus 100
according to the embodiment of the present invention includes a
microwave generator 110 and a controller 310. In addition, the
cooking apparatus 100 may further include a microwave transmitter
112.
[0052] The microwave transmitter 110 includes a frequency
oscillator 332, a level controller 334 and an amplifier 336. In
addition, the microwave generator 110 may further include a
directional coupler 338.
[0053] The frequency oscillator 332 oscillates to output microwaves
of the corresponding frequencies by frequency control signal from
the controller 310. The frequency oscillator 332 may include a
voltage controlled oscillator (VCO). The voltage controlled
oscillator (VCO) oscillates the corresponding frequency according
to voltage levels of the frequency controlled signal. For example,
as the voltage level of the frequency controlled signal is
increased, the frequency generated by being oscillated from the
voltage controlled oscillator (VCO) is higher.
[0054] The level controller 334 controls to output microwaves as
the corresponding power by a power control signal from the
controller 310. The level controller 334 may include a voltage
controlled attenuator (VCA). The voltage controlled attenuator
(VCA) performs a calibration operation to output oscillates the
corresponding frequency according to voltage levels of the
frequency controlled signal. For example, as the voltage level of
the power controlled signal is increased, the power level to be
outputted from the voltage controlled attenuator (VCA) is
higher.
[0055] The level controller 334 may output a constant power for
each of a plurality of microwaves by receiving the same power
controlled signal from controller 310 for each microwave, during
the heating period of time.
[0056] In addition, since the constant power is outputted during
the heating period of time using the microwaves, an additional
level controller 334 for controlling the power cannot be
required.
[0057] The amplifier 336 performs an amplifying operation to output
the predetermined frequency and power through the frequency
oscillator 332 and the level controller 334. The amplifier 336 may
include the solid state power amplifier (SSPA) as described above,
in particular, monolithic microwave integrated circuits (MMIC)
using a single substrate. Accordingly, the amplifier 336 can be
easily controlled by the controller 310, and the size is smaller so
that the integration of the elements may be achieved.
[0058] The directional coupler (DC) 338 transmits microwaves
amplified and outputted from the amplifier 336 to the microwave
transmitter 112 The microwaves outputted from the microwave
transmitter 112 heats the object of the cavity 134. Meanwhile, the
microwaves reflected, not absorbed from the object are again
inputted to the directional coupler 338 through the microwave
transmitter 112. The directional coupler 338 transmits the
reflected microwave to the controller 310.
[0059] Meanwhile, the microwave generator 110 may be disposed
between the directional coupler 338 and the controller 310 and may
further include DC converter (not shown) which converts the
reflected microwave into a control signal. Herein, the DC converter
(not shown) may be implemented as a diode element.
[0060] Meanwhile, the microwave generator 110 may be disposed
between the amplifier 336 and the directional coupler 338 and when
the microwave amplified from the amplifier 336 is transmitted to
the cavity 134, the microwave is passed and a separation unit (not
shown) to block the microwave reflected from the cavity 134 may be
further included. Herein, the separation unit (not shown) may be
implemented with an isolator.
[0061] Meanwhile, in addition to the frequency oscillator 332, the
level controller 334 and the amplifier 336, the directional coupler
338 may be implemented as one module. That is, all components
described above are disposed on one substrate and may be
implemented as one module. Due to the integration of the elements,
the microwave generator 110 can be easily controlled by the
controller 310.
[0062] The controller 310 controls overall operations of the
cooking apparatus. When the operating signal of the cooking
apparatus is inputted through the operating unit 107, the microwave
generator 110 is controlled to output the microwaves.
[0063] In addition, the controller 310 calculates heating
efficiency with respect to each of the plurality of microwaves
based on the microwaves reflected from the inside of the cavity
among the microwaves outputted from the microwave generator 110,
and then sets heating time with respect to each microwave during a
heating period of time according to the calculated heating
efficiency.
[0064] In this case, the controller 310 controls such that when the
heating efficiency of a first microwave among the plurality of
microwaves is higher than that of a second microwave, the heating
time of the first microwave is set to be shorter than that of the
second microwave.
[0065] Specifically, the controller 310 controls such that
frequency controlled signal is outputted and the corresponding
frequencies is oscillated in the frequency oscillator 332.
[0066] Meanwhile, the controller 310 can output the frequency
controlled signal of the different voltage levels in order to
output the microwaves having a plurality of frequencies.
Accordingly, the frequency oscillator 332 oscillates the
corresponding frequency according to the voltage level of the
inputted frequency control signal. Meanwhile, the plurality of
frequency controlled signal may be sequentially outputted from the
controller 310.
[0067] The controller 310 controls such that a power controlled
signal is outputted so that the corresponding power level may be
outputted in the frequency oscillator 334.
[0068] In this case, the controller 310 can output the same power
controlled signal with respect to the each microwave to the
microwave generator during the heating period of time. In addition,
the level controller 334 can output a constant power level
according to the inputted power controlled signal.
[0069] Meanwhile, the controller 310 may calculate the heat
efficiency based on the microwaves reflected, not absorbed to the
object of microwaves discharged to the cavity 134.
he=(Pt-Pr)/Pt [Equation 1]
[0070] Herein, Pt represents a power of the microwave discharged to
the inside of the cavity 134, Pr indicates a power of the microwave
discharged from the cavity 134 and he represents a heat efficiency
of the microwave. That is, the heating efficiency is smaller, as
the power of the reflected microwave is greater.
[0071] Meanwhile, when a plurality of microwaves is discharged into
the cavity 134, the controller 310 calculates the heat efficiency
he for each frequency of the plurality of microwaves. The heating
efficiency calculation is preferably performed in a scan period of
time among the scan period and a heating period of time within
overall cooking periods.
[0072] Meanwhile, the overall cooking periods can be performed in
the heating period of time after being performed in the scan period
of time, or in the heating period while performing in the scan
period of time. In addition, heating efficiency calculation can be
repeatedly performed in the overall cooking periods.
[0073] That is, the controller 310 can calculates the heating
efficiency he for each frequency through microwaves reflected by
sequentially discharging a plurality of microwaves into the cavity
134, among the cooking periods set by a user.
[0074] Subsequently, the controller 310 controls a discharged time
of microwaves for each frequency within the heating period of time
which is actual cooking period according to the calculated heating
efficiency he. That is, the heating efficiency he is higher, as the
discharged time is preferably shorter. Accordingly, the microwaves
can be uniformly absorbed in the heating object 140 inside the
cavity 134 for each frequency to heat the heating object 140
uniformly.
[0075] Meanwhile, the controller 310 controls such that microwaves
of the corresponding frequency may be discharged in the heating
period only when the heating efficiency he calculated for each
frequency is equal to or greater than a predetermined value. That
is, the heating object 140 can be effectively heated uniformly by
actually excluding microwaves of the frequencies that the heating
efficiency he is significantly lower.
[0076] Meanwhile, the discharge of the plurality of microwaves can
be sequentially performed in time.
[0077] Meanwhile, according to another embodiment of the present
invention, the controller 310 can use the microwaves when heating
by selecting the microwaves of frequencies corresponding to the
heating efficiency down adjusted by setting value from the maximum
heating efficiency when the microwaves of frequencies that a
heating efficiency is equal to or greater than a threshold value,
based on the microwaves reflected from the inside of the cavity
among the outputted microwaves, do not exist.
[0078] In this case, the controller 310 controls such that in the
scan period of time among the cooking process using microwaves
including the scan period of time and the heating period of time,
microwaves of frequencies to be used during the heating period of
time can be selected.
[0079] Meanwhile, the controller 310 such that when the microwaves
having frequencies that a heating efficiency is equal to or greater
than a threshold value, based on the microwaves reflected among the
microwaves outputted to the cavity, do not exist, the threshold
value can be down adjusted
[0080] In this case, the controller controls such that after the
threshold value is down adjusted, the microwaves having frequencies
to be used when heating according to the down adjusted threshold
value can be selected by re-performing the scan process.
[0081] Meanwhile, according to the embodiment of the present
invention, the controller 310 controls such that heating efficiency
for each of the plurality of microwaves is calculated based on the
microwaves reflected from the inside of the cavity among the
microwaves outputted from the microwave generator 110, a heating
mod is selected according to the calculated heating efficiency and
the same energy is supplied by the selected heating mode.
[0082] In this case, the controller 310 can select the heating mode
on the basis of a peak value of the calculated heating efficiency.
Accordingly, the controller 310 can control such that the same
energy is supplied with respect to each of microwaves having
frequencies corresponding to the peak value of the calculated
heating efficiency.
[0083] Meanwhile, the controller 310 can select the heating mode on
the basis of a predetermined threshold value for the calculated
heating efficiency.
[0084] Accordingly, the controller 310 controls such that the total
energy is equally supplied by each of the selected heating modes by
supplying the heating energy to be inversely proportional to the
frequency range for each of the selected heating modes.
[0085] That is, the controller 310 controls such that the total
energy may be equally supplied by each of the selected heating
modes by reducing the heating energy when the frequency range of
the selected heating mode is wide and by increasing the heating
energy when the frequency range of the selected heating mode is
narrow.
[0086] Meanwhile, the control unit 310 can control to display the
overall operation states of the cooking apparatus through a display
unit 105. For example, when the current period of time is the scan
period of time among the entire cooking period of time, the display
can be performed through the display unit 105. Further, when
current period of time is the actual heating period of time, the
display can be implemented. In addition, various types of display
functions such as the remaining time of the entire cooking period
of time can be performed.
[0087] The power supply 114 outputs a high voltage to the microwave
generator 110 by boosting power inputted to the cooking apparatus
100 The power supply 114 may be implemented as a high voltage
transformer or an inverter. Meanwhile, the power supply 114 can
generate and supply a predetermined control power for the control
operation of a controller (not shown).
[0088] Meanwhile, the controller 310 and the microwave generator
110 can be implemented as one module. That is, the controller 310
and the microwave generator 110 can be implemented by being
integrated on one substrate.
[0089] Referring to the mentioned configuration, a heating time
control process for each frequency according to the present
invention is described below.
[0090] The controller 310 outputs a frequency control signal for
sweeping microwaves of the various frequencies to the frequency
oscillator 332 of the microwave generator 110 during the scan
period of time.
[0091] The frequency oscillator 332 generates a plurality of
microwaves according to the frequency control signal inputted from
the controller 310.
[0092] The level controller 334 controls levels corresponding to
amplitudes of the microwaves generated by the frequency oscillator
332 according to a power control signal inputted from the
controller 310. In this case, the power control signal outputted to
the level controller 334 by the controller 500 may be provided as
the same signal for all microwaves to be used in the sweep
process.
[0093] The amplifier 336 amplifies microwaves that the level is
adjusted, a separation unit (not shown) provides the amplified
microwaves to a directional coupler 520 and the directional coupler
338 provides microwaves provided by the separation unit (not shown)
to the microwave transmitter 112.
[0094] The microwave transmitter 112 outputs microwaves provided by
the directional coupler 520 to the cavity 134.
[0095] Meanwhile, when a portion of microwaves outputted from the
cavity 134 is reflected, the directional coupler 338 provides the
reflected microwaves to a DC converter (not shown).
[0096] The DC converter (not shown) outputs a feedback signal
converting the portion of microwaves reflected from the cavity 134
into DC to the controller 310.
[0097] The controller 310 calculates the heating efficiency for
each of a plurality of microwaves based on the inputted feedback
signal. In this case, the controller 310 can determine that the
heating efficiency is higher when the feedback signal for each of
microwaves is small.
[0098] In addition, the controller 310 controls to vary the heating
time for each of microwaves, that is, the discharge time for each
of microwaves during the heating period of time, according to the
heating efficiency for each of calculated microwaves. In this time,
the controller 310 controls such that the heating time is short
with respect to the microwave that the calculated heating
efficiency is high and the heating time is longer with respect to
the microwave that the calculated heating efficiency is low.
[0099] For example, as a result of the calculation of the heating
efficiency, when the heating efficiency with respect to the
microwave of frequency f5 is low, the controller 310 controls such
that the heating time with respect to the microwave of frequency f5
is relatively long during the heating period Th of time shown in
FIG. 4, and when the heating efficiency with respect to the
microwave of frequency f3 is high, the controller 310 controls such
that the heating time with respect to the microwave of frequency f3
is relatively short during the heating period Th of time.
[0100] In this case, the heating period Th of time shown in FIG. 4
can be determined by the user's operation or a kind of object
inside the cavity 134, a predetermined gap time may be between the
scan period Ts of time and the heating period of time Th, and the
heating period Th of time can be maintained to be longer than the
scan period Ts. In addition, the scan period of time and the
heating period of time can be repeatedly performed during the
cooking process using microwaves.
[0101] That is, the controller 310 controls such that the frequency
control signal for generating microwaves of the corresponding
frequency is provided to the frequency oscillator 332 of the
microwave generator 110 during a short time with regard to
microwaves that the heating efficiency is high and the frequency
control signal for generating microwaves of the corresponding
frequency is provided to the frequency oscillator 332 of the
microwave generator 110 during a long time with regard to
microwaves that the heating efficiency is low.
[0102] The frequency oscillator 332 generates the corresponding
microwaves according to the frequency control signal provided from
the controller 310.
[0103] The level controller 334 controls levels corresponding to
amplitudes of the microwaves generated by the frequency oscillator
332 according to a power control signal provided from the
controller 310. In this case, the power control signal provided to
the level controller 334 by the controller 310 may be provided as
the same signal for all microwaves to be used in the heating period
of time.
[0104] The amplifier 336 amplifies microwaves that the level is
adjusted, a separation unit (not shown) provides the amplified
microwaves to a directional coupler 338, the directional coupler
338 provides microwaves provided by the separation unit (not shown)
to the microwave transmitter 112 and the microwave transmitter 112
outputs microwaves provided by the directional coupler 338 to
cavity 134.
[0105] Accordingly, an uniform power can be transmitted to an
object inside a cavity by decreasing a heating time for microwaves
having a high heating efficiency and increasing the heating time
for microwaves having a low heating efficiency.
[0106] FIG. 5 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to an embodiment of
the present invention; FIG. 6 is a view illustrating a heating
efficiency for each of frequency according to an embodiment of the
present invention; and FIG. 7 is a view illustrating a heating time
for each of frequency according to an embodiment of the present
invention.
[0107] Referring to FIG. 5, a controller of the cooking apparatus
using microwaves according to the present invention detects a
heating efficiency for each of frequencies as shown in FIG. 6 by
sweeping the microwaves of various frequencies (S502).
[0108] That is, the controller sequentially outputs the frequency
control signal to the frequency oscillator of the microwave
generator and the frequency oscillator generates microwaves of the
corresponding frequency according to the frequency control signal
outputted from the controller.
[0109] The level controller of the microwave generator controls
levels corresponding to amplitudes of the microwaves generated by
the frequency oscillator according to a power control signal
provided from the controller.
[0110] The amplifier provided in the microwave generator amplifies
microwaves that the level is adjusted, and a separation unit
provided in the microwave generator provides the amplified
microwaves to a directional coupler provided in the microwave
generator.
[0111] The directional coupler provides microwaves provided by the
separation unit to the microwave transmitter and the microwave
transmitter outputs microwaves provided by the directional coupler
to cavity.
[0112] In addition, when a portion of microwaves outputted from the
cavity through microwave transmitter is reflected, the directional
coupler provides the reflected microwaves to a DC converter and the
DC converter provides a feedback signal converting the portion of
the provided microwaves into DC to the controller.
[0113] The controller calculates the heating efficiency for each of
a plurality of microwaves based on the provided feedback signal. In
this case, the controller can calculates that the heating
efficiency is higher when the feedback signal for each of
microwaves is small.
[0114] Meanwhile, the controller can store the calculated heating
efficiency for each of the frequency through a storage unit
(S504).
[0115] In addition, the controller determines the heating time for
each of microwaves according to the heating efficiency for each of
detected microwaves (S506) That is, the controller may control such
that the heating time is short with respect to the microwave that
the calculated heating efficiency is high and the heating time is
longer with respect to the microwave that the calculated heating
efficiency is low.
[0116] For example, referring to FIGS. 6 and 7, since the heating
efficiency with respect to the microwave of frequency 12 is lower
than the heating efficiency with respect to the microwave of
frequency f6, the controller can determine that the heating time
with respect to the microwave of frequency 12 is relatively longer
than the heating time with respect to the microwave of frequency
f6. In addition, a predetermined gap time may be between the
heating times for each of frequencies.
[0117] In this case, the controller may use only microwaves f2, f5,
f6 and f7 of frequencies that the calculated heating efficiency is
equal to or greater than the threshold in the heating process.
[0118] In addition, the controller controls to vary the heating
time for each of frequencies according to the heating time for each
of determined microwaves as described above (S508).
[0119] That is, the controller controls such that the frequency
control signal for generating microwaves of the corresponding
frequency is outputted to the frequency oscillator of the microwave
generator during a short time with regard to microwaves that the
heating efficiency is high and the frequency control signal for
generating microwaves of the corresponding frequency is provided to
the frequency oscillator of the microwave generator during a long
time with regard to microwaves that the heating efficiency is
low.
[0120] The frequency oscillator provided in the microwave generator
generates the corresponding microwaves according to the frequency
control signal inputted from the controller.
[0121] The level controller of the microwave generator controls
levels corresponding to amplitudes of the microwaves generated by
the frequency oscillator according to a power control signal
provided from the controller. In this case, the power control
signal provided to the level controller by the controller 310 may
be provided as the same signal for all microwaves to be used in the
heating period of time.
[0122] The amplifier provided in the microwave generator amplifies
microwaves that the level is adjusted, a separation unit provided
in the microwave generator provides the amplified microwaves to a
directional coupler provided in the microwave generator, the
directional coupler microwaves provided by the separation unit to
the microwave transmitter, and the microwave transmitter outputs
microwaves provided by the directional coupler to the cavity.
[0123] Accordingly, an uniform power can be transmitted to an
object inside a cavity by decreasing a heating time for microwaves
having a high heating efficiency and increasing the heating time
for microwaves having a low heating efficiency to heat the object
inside the cavity uniformly.
[0124] FIG. 8 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to another embodiment
of the present invention; and FIG. 9 is a view illustrating an
example of a heating efficiency for each of frequencies.
[0125] Referring to FIG. 8, the controller of the cooking apparatus
using microwaves according to the present invention generates the
microwaves of a variety of frequencies to output the generated
microwaves to the cavity (S602).
[0126] Subsequently, the controller detects the heat efficiency for
each of frequencies as shown in FIG. 9 based on the microwaves
reflected from the cavity among the outputted microwaves
(S604).
[0127] That is, the controller sequentially outputs the frequency
control signal to the frequency oscillator of the microwave
generator and the frequency oscillator generates microwaves of the
corresponding frequency according to the frequency control signal
outputted from the controller.
[0128] The level controller of the microwave generator controls
levels corresponding to amplitudes of the microwaves generated by
the frequency oscillator according to a power control signal
provided from the controller.
[0129] The amplifier provided in the microwave generator amplifies
microwaves that the level is adjusted, and a separation unit
provided in the microwave generator provides the amplified
microwaves to a directional coupler provided in the microwave
generator.
[0130] The directional coupler provides microwaves transmitted by
the separation unit to the microwave transmitter and the microwave
transmitter outputs microwaves provided by the directional coupler
to the cavity.
[0131] In addition, when a portion of microwaves outputted from the
cavity through microwave transmitter is reflected, the directional
coupler provides the reflected microwaves to a DC converter and the
DC converter provides a feedback signal converting the portion of
the provided microwaves into DC to the controller.
[0132] The controller calculates the heating efficiency for each of
a plurality of microwaves based on the provided feedback signal. In
this case, the controller can calculates that the heating
efficiency is higher when the feedback signal for each of
microwaves is small.
[0133] Meanwhile, the controller confirms whether microwaves having
the calculated heating efficiency greater than the threshold exist
(S606).
[0134] As a result of the confirmation, when microwaves having the
calculated heating efficiency greater than the threshold do not
exist, the controller down adjusts the threshold by changing a
first threshold to a second threshold (S620).
[0135] In addition, the controller controls such that after the
threshold value is down adjusted, the microwaves having frequencies
to be used when heating according to the down adjusted threshold
value can be selected by re-performing the scan process (S602 to
S606).
[0136] Meanwhile, the controller controls such that the object of
the inside of the cavity can be heated by using microwaves of
selected frequencies (S608).
[0137] In addition, the controller compares a temperature of the
object of the inside of the cavity with the set value after heating
(S610), determines as the heating is complete when the temperature
is greater than the set value, and re-performs the processes (S602
to S608) when the temperature is lower than the set value.
[0138] Accordingly, as shown in FIG. 9, when using the first
threshold, there are no usable microwaves when heating, but when
using the second threshold, a microwave of the frequency f2 and a
microwave of the frequency f8 can be used when heating.
[0139] FIG. 10 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to another embodiment
of the present invention; and FIG. 9 is a view illustrating another
example of a heating efficiency for each of frequencies.
[0140] Referring to FIG. 10, the controller of the cooking
apparatus using microwaves according to the present invention
generates the microwaves of a variety of frequencies to output the
generated microwaves to the cavity (S702).
[0141] Subsequently, the controller detects the heat efficiency for
each of frequencies as shown in FIG. 11 based on the microwaves
reflected from the cavity among the outputted microwaves
(S704).
[0142] That is, the controller sequentially outputs the frequency
control signal to the frequency oscillator of the microwave
generator and the frequency oscillator generates microwaves of the
corresponding frequency according to the frequency control signal
outputted from the controller.
[0143] The level controller of the microwave generator controls
levels corresponding to amplitudes of the microwaves generated by
the frequency oscillator according to a power control signal
provided from the controller.
[0144] The amplifier provided in the microwave generator amplifies
microwaves that the level is adjusted, and a separation unit
provided in the microwave generator provides the amplified
microwaves to a directional coupler provided in the microwave
generator.
[0145] The directional coupler provides microwaves provided by the
separation unit to the microwave transmitter and the microwave
transmitter outputs microwaves provided by the directional coupler
to cavity.
[0146] In addition, when a portion of microwaves outputted from the
cavity through microwave transmitter is reflected, the directional
coupler provides the reflected microwaves to a DC converter and the
DC converter provides a feedback signal converting the portion of
the provided microwaves into DC to the controller.
[0147] The controller calculates the heating efficiency for each of
a plurality of microwaves based on the provided feedback signal. In
this case, the controller can calculates that the heating
efficiency is higher when the feedback signal for each of
microwaves is small.
[0148] Meanwhile, the controller confirms whether microwaves that
the calculated heating efficiency is greater than the threshold
exist (S706).
[0149] As a result of the confirmation, when microwaves having the
calculated heating efficiency greater than the threshold do not
exist, the controller controls such that the microwave of the
frequency corresponding to heating efficiency down adjusted by the
set value from the maximum of heating efficiency is selected to be
used when heating (S720).
[0150] For example, as shown in FIG. 11, the controller controls
such that when the microwave having the frequency that the heating
efficiency is greater than the threshold is not found from the
first threshold A, the microwave of the each of the corresponding
frequencies f1, f2, f3, f7, f8, f9 from the second threshold C down
adjusted by the set value from the maximum of heating efficiency B
among the calculated heating efficiencies is selected to be used
when heating.
[0151] Meanwhile, the controller controls such that the object of
the inside of the cavity can be heated by using microwaves of
selected frequencies (S708).
[0152] In addition, the controller compares a temperature of the
object of the inside of the cavity with the set value after heating
(S710), determines as the heating is complete when the temperature
is greater than the set value (S712), and re-performs the processes
(S702 to S708) when the temperature is lower than the set
value.
[0153] FIG. 12 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to another embodiment
of the present invention; FIG. 13 is a view illustrating a heating
efficiency for each of frequency; and FIG. 14 is a view
illustrating a heating energy for each of heating modes according
to FIG. 13.
[0154] Referring to the drawings, the controller of the cooking
apparatus using microwaves according to the present invention can
calculate an efficiency characteristic function (for example,
S-parameter function or efficiency function) (S804) as shown in
FIG. 13 by sweeping microwaves of a variety of frequencies and
measuring a transmitting efficiency (S802).
[0155] In addition, the controller of the cooking apparatus using
microwaves selects a firs heating mode, a second heating mode, a
third heating mode and a fourth heating mode corresponding to each
of frequencies f1, f2, f3 and f4 and choose peak frequencies f1,
12, f3 and f4 for each mode (S806).
[0156] In addition, the controller of the cooking apparatus using
microwaves controls to supply the same energy for the chosen each
mode as shown in FIG. 14.
[0157] Subsequently, the controller of the cooking apparatus using
microwaves confirms whether the heating is completed (S810), and
then ends the control when the heating with regard to the object
inside the cavity is completed.
[0158] Accordingly, the heating mode can be selected by
representing a resonance mode by each peak from the S-parameter
function or the efficiency function and by uniformly forming
various heating modes without representing a heating pattern of the
specific heating mode by an non-uniformly heating after the same
energy is supplied for each heating mode to optimize a uniform
heating.
[0159] FIG. 15 is a flow chart illustrating a control method of a
cooking apparatus using microwaves according to another embodiment
of the present invention; FIG. 16 is a view illustrating a heating
efficiency for each of frequency; and FIG. 17 is a view
illustrating a heating energy for each of heating modes according
to FIG. 16.
[0160] Referring to the drawings, the controller of the cooking
apparatus using microwaves according to the present invention can
calculate an efficiency characteristic function (for example,
S-parameter function or efficiency function) (S904) as shown in
FIG. 16 by sweeping microwaves of a variety of frequencies and
measuring a transmitting efficiency (S902).
[0161] In addition, the controller of the cooking apparatus using
microwaves selects frequency ranges (that center frequencies are
corresponded to f1, f2, f3 respectively) to meet a reference value
as a first heating mode, a second heating mode, a third heating
mode and a fourth heating mode and choose frequencies to meet the
reference value for each heating mode, as shown in FIG. 16.
(S906).
[0162] In addition, the controller of the cooking apparatus using
microwaves controls to supply the same energy for the chosen each
mode as shown in FIG. 17. (S908).
[0163] That is, the controller of the cooking apparatus using
microwaves controls such that the energy may be equally supplied by
each of the selected heating modes by reducing the heating energy
when the frequency range of the selected heating mode is wide (for
example, when the center frequency is f1 as shown in FIG. 17) and
by increasing the heating energy when the frequency ranges of the
selected heating mode is narrow (for example, when the center
frequency is f2 as shown in FIG. 17) Accordingly, each area of
three kinds of heating modes may be the same as shown in FIG.
17.
[0164] Subsequently, the controller of the cooking apparatus using
microwaves confirms whether the heating is completed (S910), and
then ends the control when the heating with regard to the object
inside the cavity is completed.
[0165] Accordingly, the heating mode that satisfies the reference
value of the S-parameter function is selected, and the same energy
is supplied for each heating mode and then various heating modes
can be uniformly formed without representing a heating pattern of
the specific heating mode to optimize a uniform heating.
[0166] FIG. 18 is a view illustrating another example of a heating
efficiency for each frequency; FIG. 19 is a view illustrating a
heating energy for each heating mode according to FIG. 18; FIG. 20
is a view illustrating a heating pattern corresponding to a first
heating mode shown in FIG. 19; FIG. 21 is a view illustrating a
heating pattern corresponding to a second heating mode shown in
FIG. 19; FIG. 22 is a view illustrating when generally forming a
first heating mode and a second heating mode at the same time; and
FIG. 23 is a view illustrating when generally forming a first
heating mode and a second heating mode at the same time according
to the present invention.
[0167] Referring to the drawings, the controller of the cooking
apparatus using microwaves according to the present invention can
calculate an efficiency characteristic function (for example,
S-parameter function) as shown in FIG. 18 by sweeping microwaves of
a variety of frequencies and measuring a transmitting
efficiency.
[0168] In addition, the controller of the cooking apparatus using
microwaves selects frequency ranges (that center frequencies are
corresponded to fl and f2, respectively) to meet a reference value
as a first heating mode and a second heating mode and supplies the
same energy for the chosen each heating mode, as shown in FIG.
18.
[0169] Accordingly, the standard deviation of a heating pattern
shown in FIG. 23 is less than that of a heating pattern shown in
FIG. 22 and the difference between the maximum and the minimum
values is small, and then the first heating mode and the second
heating mode can be uniformly formed to optimize a uniform heating
In this case, the standard deviation may be a standard deviation of
a pixel and a temperature.
[0170] Those skilled in the art will understand that the present
invention can be implemented as other concrete forms without
changing the inventive concept or essential features. Therefore,
these embodiments as described above are only proposed for
illustrative purposes and do not limit the present invention. It
will be apparent to those skilled in the art that a variety of
modifications and variations may be made without departing the
spirit and scope of the present invention as defined by the
appended claims. Further, such modifications and variations should
not be understood independently from the technical idea or
perspective of the present invention.
* * * * *